Revert of Add OnDisplayMetricsChanged in DisplayObserver.

ash/touch/touch_observer_hud.cc

Index: ash/touch/touch_observer_hud.cc
diff --git a/ash/touch/touch_observer_hud.cc b/ash/touch/touch_observer_hud.cc
index f3f0b352708b819b5dadfced4084bd2fe24802bc..87d6d4ee50d5c0f3c17807de8f0b9fc5de3d70e0 100644
--- a/ash/touch/touch_observer_hud.cc
+++ b/ash/touch/touch_observer_hud.cc
@@ -86,20 +86,18 @@
   delete this;
 }
 
+void TouchObserverHUD::OnDisplayBoundsChanged(const gfx::Display& display) {
+  if (display.id() != display_id_)
+    return;
+  widget_->SetSize(display.size());
+}
+
 void TouchObserverHUD::OnDisplayAdded(const gfx::Display& new_display) {}
 
 void TouchObserverHUD::OnDisplayRemoved(const gfx::Display& old_display) {
   if (old_display.id() != display_id_)
     return;
   widget_->CloseNow();
-}
-
-void TouchObserverHUD::OnDisplayMetricsChanged(const gfx::Display& display,
-                                               uint32_t metrics) {
-  if (display.id() != display_id_ || !(metrics & DISPLAY_METRIC_BOUNDS))
-    return;
-
-  widget_->SetSize(display.size());
 }
 
 #if defined(OS_CHROMEOS)